DTC P1177: Fuel Mass Flow Rate Rich

NOTE: After each repair, clear DTCs. See CLEARING CODES/PCM RESET PROCEDURE under SELF-DIAGNOSTIC SYSTEM. Turn ignition off and then on. Read DTCs to verify repair is complete. For DLC and PCM connector terminal identification, see CONNECTOR IDENTIFICATION . For wiring diagrams, see WIRING DIAGRAMS .

Using scan tool, read DTCs. If DTC P1177 is present, turn ignition off. Inspect fuel system pressure and repair as necessary. If fuel system pressure is okay, inspect fuel return pipe for blockage and repair as necessary. If fuel return pipe is okay, check for leaks in vacuum hose to regulator. Repair hose as necessary.
If vacuum hose is okay, check for fuel injector leaks. Repair as necessary. If fuel injectors are okay, check for MAF sensor or HO2S DTCs. Repair as necessary. If MAF or HO2S DTCs are not present, clear DTCs. Turn ignition off and then on. Read DTCs. If DTC P1177 is not present, repair is complete. If DTC P1177 is present, replace PCM.